The present invention relates to ballistic armor helmets in general and ballistic armor helmets constructed of more than one piece in particular.
From at least the earliest days of recorded history soldiers have worn helmets to protect their head from injuries from blows and projectiles. Even today a major location of lethal battlefield injuries remains the head. There is a continued importance of maximizing protection for the head in the form of a helmet. Helmets have always had two problems which limited their effectiveness: one is weight, the other is comfort. If the helmet weighs too much it interferes with movement of the head, if the helmet is too uncomfortable it is difficult to make the soldiers wear them at all times. In modern times the problem of greater ballistic protection without debilitating weight has been addressed through the use of composite armor fabricated from ballistic fabrics such as Kevlar® material, a type of Aramid fiber ballistic Nylon®, a meta-aramid such as Nomex® fibers, Twaron® a para-aramid fiber, and Spectra® fibers, an extended-chain ultra-high molecular weight polyethylene fiber, in a matrix of thermoset or thermoplastic material, or using structural reaction injection molding (RIM) technology. Comfort, particularly thermal comfort, can be addressed by limiting the areas of the head protected.
The downside of composite ballistic armor is substantial additional cost, and the downside of limiting the area of head protection is greater vulnerability to lethal or debilitating head injury. With weight controlled through the use of a lightweight ballistic fiber composite armor the major factor in comfort, particularly in hot climates, is the natural insulating and heat retention function of a hat or helmet. A large fraction of body cooling takes place through the head. To the extent a helmet prevents heat loss from the head, particularly in warm climates, real problems of considerable discomfort and even heat exhaustion or heat stroke can result. What is needed is a ballistic armored helmet which is less costly, cooler, and provides greater coverage of a soldier's head. If these three factors could be combined their benefits would be more than additive, producing synergistic reduction in battlefield losses. A less costly helmet is available to more soldiers, a cooler helmet is worn more consistently and results in less head-related casualties, and a helmet of greater coverage provides greater protection.